A.D. 2087 - the United Lunar Empire Giganos wages war on the Earth Federation Military to take control of the planet and establish a "rebirth" of the human race. During an invasion of a colony by Giganos' forces, three civilian men stumble upon a trio of top-secret Metal Armor units called "Dragonars" and pilot them to combat the enemy forces
西历2087年,地球和宇宙正被炽热的烈炎包围着。为提倡地球人类再生,在月球树立起旗帜的统一帝国吉卡诺斯的独裁政权,以创立宇宙新秩序为口号,向地球联合军挑起了战火。
住在殖民地阿露卡特的三名少年,偶然得到地球联合军从吉卡诺斯盗取的三台秘密开发的新型MA“D兵器”的启动磁碟而登录成为了它们的唯一驾驶员。故事也由此展开……